How the price is determined from actual transactions
The most common mistake an owner brings to us is a property price estimate built on the neighbours’ adverts (inzerát): three listings from one street, an average, done. But an advert is the seller’s wish, not a completed deal. This text shows how the price is calculated from completed sales — where they come from, how they are selected and how they are adjusted for the differences between flats.
An advert is a wish, a transaction is evidence
The difference between the asking price (nabídková cena) and the achieved price (realizovaná cena) can be measured. According to completed sales for the first quarter of 2026, Holešovice stood at CZK 164,474/m²; according to the price maps (cenová mapa) for April 2026, it stood at CZK 193,730/m². A difference of CZK 29,256 per metre, i.e. 17.8 %, which for a 78 m² flat comes to over two million crowns.
Neither number lies; they differ in methodology. The first is based on the prices at which flats actually changed owner, the second on listings and on the price map’s model. Anyone who picks the higher one because they like it better has gained not information, only confirmation.
With the neighbours’ adverts there is also a distortion that is easy to overlook: what the owner sees is what is left over. Flats that sold quickly and well have disappeared from the adverts; what remains are those that have been hanging there for four months because their price is wrong. And the advertised price has no other side — it is one person’s claim, whereas the price in a purchase agreement (kupní smlouva) is an agreement between two people, one of whom paid.
A property price estimate rests on four inputs
The method is old and boring: the comparative approach. The prices of completed sales of similar flats are adjusted for their differences from the flat being valued, and a range is derived from the adjusted values. The whole art lies in what “similar” means and what “adjust” means. Do not confuse this with valuation under the regulations: there, under § 8(3) of Act No. 151/1997 Coll., on Property Valuation (zákon o oceňování majetku), the price of a unit is determined by the cost or the comparative method and calculated using the formulas of Valuation Decree No. 441/2013 Coll. (oceňovací vyhláška), not from actual sales.
A precisely described subject. Before anything is looked up on the market, the title block (popisové pole) of the flat is written up: layout (dispozice), floor area (podlahová plocha) according to the owner’s declaration (prohlášení vlastníka), storey (podlaží) and lift (výtah), orientation, type and year of the building, condition, cellar (sklep), parking space (stání), balcony (balkon), form of ownership, energy performance class (energetická třída). Each of these items will shortly reappear as an adjustment. What is not in the title block cannot be in the price.
Title deed (list vlastnictví). It is read before the market. Part B contains the unit and the share in the common parts (podíl na společných částech), recorded as a fraction, for example 6532/258740 — it determines both the amount paid into the repair fund (fond oprav) and the weight of the vote at the assembly (shromáždění). Part C states what encumbers the flat: a lien (zástavní právo), enforcement proceedings (exekuce), an easement (věcné břemeno). Part E contains the title of acquisition (nabývací titul) and the date from which the holding period test (časový test) for income tax (daň z příjmů) runs. Legal defects, however, are not adjusted by percentages: a lien is not a five per cent discount, it is a condition in the agreement and a settlement procedure through escrow (úschova).
Completed transactions. The whole of the next section is about them.
A range, not a number. The output is not a single amount accurate to the nearest ten thousand, but a band within which the launch price (vstupní cena) is chosen, depending on whether the owner is buying time or the maximum.
Where actual transactions come from
Prices from purchase agreements are entered in the Land Registry (katastr nemovitostí) and are not secret. They have been recorded since 1 January 2014, and two reports can be pulled via remote access (dálkový přístup): Data on achieved property prices by property (Údaje o dosažených cenách nemovitostí podle nemovitostí, item 4021) and by proceedings (podle řízení, item 4022). Each output costs CZK 50 under Annex 4 to Decree No. 358/2013 Coll. (vyhláška). For five comparable sales you pay at most CZK 250 — that is the entire budget for the part of the work that gets talked about most.
What the report contains and what it does not
It contains the price from the purchase agreement (for a joint sale, the price for the whole group of properties) and the identification of the unit, the deed and the proceedings. Nothing else. It does not contain the condition of the bathroom, the storey in relation to the lift, whether the flat faces the inner courtyard (vnitroblok) or the street, the noise from the arterial road (magistrála), or whether a kitchen worth three hundred thousand stayed in the price. The report cannot value a flat by itself; what it can do is verify whether the price you consider the market price has ever actually happened on this street.
That is why sales are excluded from the report. A sale well below the median of the cadastral area (katastrální území) that you cannot explain by condition, storey or size is usually a transfer between relatives, a settlement of joint marital property (vypořádání společného jmění) or the sale of a share, not a market deal.
Price maps and aggregators are good for one thing: telling you quickly which band a neighbourhood moves in. For a specific flat they are poor, because a neighbourhood median is an average of disparate things — the figure for Vršovice hides both a studio flat in a courtyard wing and a large flat facing a park. How far apart the neighbourhoods are is discussed in the text on where to live in Prague and where to invest.
The third source is our own records of closed deals. Compared with the Land Registry, they have an advantage that cannot be bought: for our own sales we know what condition the flat was in, because we stood in it. For someone else’s transaction, the condition has to be estimated.
How five comparable sales are selected
The selection decides the result more than the adjustments themselves. The criteria we use:
- The same cadastral area, or a neighbouring one with demonstrably the same kind of buildings. Not “Prague 10” — that is a postal detail, not a market.
- The same building type. A tenement building (činžovní dům) from 1900–1940, a panel building (panelový dům), a new build (novostavba) after 2010. Mixing them means producing an average of three different products.
- A sale within the last twelve months. Older ones only when there is nothing else to choose from.
- Area within ±25 % of the flat being valued.
- The same product. A flat in personal ownership (osobní vlastnictví) is not compared with a cooperative share (družstevní podíl).
Three transactions are the minimum, five to eight the working number. When a neighbourhood does not have even three, the method does not apply, and it is more honest to say so than to fill in the difference by feel.
Seven adjustments and how they are calculated
Each transaction is converted to a price per metre and shifted by its differences from the flat being valued. Apart from the time adjustment, which is based on public statistics, the coefficients below are model values, and in an actual calculation they differ from neighbourhood to neighbourhood.
- Time. Year-on-year growth in achieved prices of older flats was 11.5 % in the first quarter of 2026. Converted to a monthly figure — the twelfth root of 1.115 minus one — that is 0.9 % per month. A transaction six months old is shifted 5.4 % upwards.
- Storey and lift. Ground floor (přízemí) −6 %, third storey and above without a lift −5 %, top storey with a lift +3 %.
- Condition. Original condition compared with partial renovation −12 %, complete renovation +8 %.
- Size. A smaller flat has a higher price per metre: ±1.5 % on the unit price for every 10 m² of difference.
- Outdoor space. Balcony +3 %. A terrace (terasa) and a front garden (předzahrádka) are valued separately; a flat rate does not work for them.
- Ancillary spaces (příslušenství). Cellar ±2 %. A parking space is adjusted by an absolute amount, not a percentage — CZK 250,000 in the model below — because its value does not depend on the price of the flat.
- Type and age of the building. A new build after 2010 compared with a tenement building from the thirties +7 % to +12 % depending on the standard.
And then the rule that does most of the real work: add up the adjustments in absolute value. When the gross sum exceeds 20 %, the transaction is not comparable and does not belong in the calculation. Comparability is not measured by layout or address; it is measured by how much you had to move the price before you arrived at your flat.
Model comparison of five transactions with adjustments
Flat being valued: Vršovice, 3+kk (three rooms plus a kitchenette), 78 m², 4th storey with a lift, brick tenement building from 1931, partial renovation (bathroom and services 2016, original kitchen), cellar, no balcony, personal ownership. Valuation date September 2026.
The five transactions below are a model set built on the Vršovice median for the first quarter of 2026 (CZK 152,078/m²); the individual sales are illustrative. The figures in the columns, however, are calculated exactly as described above.
| # | What sold | Sold | Purchase price | CZK/m² | Adjustments | Sum | Gross sum | Adjusted price |
|---|---|---|---|---|---|---|---|---|
| 1 | 3+kk, 74 m², 2nd storey with lift, renovated, cellar, balcony | 03/2026 | CZK 11,600,000 | 156,757 | time +5.4; size −0.6; condition −8; balcony −3 | −6.2 % | 17.0 % | CZK 147,038/m² |
| 2 | 3+1 (separate kitchen), 82 m², ground floor, original condition, cellar, no balcony | 06/2026 | CZK 11,070,000 | 135,000 | time +2.7; size +0.6; storey +6; condition +12 | +21.3 % | 21.3 % | excluded |
| 3 | 2+kk, 58 m², 5th storey with lift, renovated, no cellar, balcony | 05/2026 | CZK 9,570,000 | 165,000 | time +3.6; size −3; condition −8; balcony −3; cellar +2 | −8.4 % | 19.6 % | CZK 151,140/m² |
| 4 | 3+kk, 80 m², 3rd storey without lift, partial renovation, cellar | 11/2025 | CZK 11,200,000 | 140,000 | time +9; size +0.3; lift +5 | +14.3 % | 14.3 % | CZK 160,020/m² |
| 5 | 4+kk, 96 m², 6th storey with lift, new build 2019, cellar and parking space | 07/2026 | CZK 16,320,000 | 170,000 | time +1.8; size +2.7; building type −12; storey −3; parking space −CZK 250,000 | −10.5 % | 19.5 % | CZK 149,546/m² |
What the table shows. Before the adjustments, the five sales spread from CZK 135,000 to CZK 170,000/m², a band of CZK 35,000 per metre. Nothing can be built on a range like that.
Transaction No. 2 looked the best — the same neighbourhood, the same size, almost the same layout — and a gross sum of adjustments of 21.3 % excluded it: a ground-floor flat in original condition is a different product, even if it is two buildings away. Conversely, No. 5, the 4+kk in a new build that most people would exclude straight away, passed with 19.5 % and after the adjustments sits in the middle of the field.
Of the four remaining values, the median is CZK 150,343/m² and the range CZK 147,038–160,020/m². Of the CZK 35,000 per metre, just under 13,000 is left. The centre of gravity lies around CZK 150,000/m², which for 78 m² makes CZK 11,700,000.
A check against the neighbourhood: the Vršovice median for the first quarter of 2026 was CZK 152,078/m², i.e. CZK 11,862,084 for the same area. The estimate lies 1.4 % below it, which fits a flat with an original kitchen and no balcony. If it had come out ten per cent above the neighbourhood, we would be looking for an error in the inputs, not a reason to celebrate.
If the price were set from three neighbours’ adverts at around CZK 175,000/m², it would come out at CZK 13,650,000. The difference from the transaction-based estimate is CZK 1,950,000 — and that is exactly the amount that will keep anyone from looking at the flat for the first three months.
From the range to the launch price
A range is not a price; it is a boundary. Within it, a single question decides: is the owner buying time, or the maximum?
For the model flat, the launch price would be CZK 11,900,000, i.e. CZK 152,564/m². It is above the centre of gravity and within the range. That headroom is for one negotiation, not for three successive discounts — an inflated price “so there is room to come down” exposes the flat to the whole market in the first two weeks at an amount the market will reject. How preparation, price and the launch of advertising follow on from one another is described in the text on how to sell a flat in Prague.
The price also has a built-in checkpoint: after fourteen days, viewings are counted, not impressions. If there are noticeably few of them for the given location and layout, the error is in the price, not in the photos — the photos decide the click-through, the price decides who gets in touch at all.
Where this approach fails
The time adjustment is the weakest link in the calculation. For transaction No. 4, nine percentage points out of fourteen rest on a single number — year-on-year growth for the whole of Prague, which did not happen equally in every building. The older the transaction, the more of the result comes from the model and the less from the actual deal — and the less weight we give it.
The coefficients are not a published standard. Those in this text are model values, and someone else will arrive at a different number. Anyone who claims that a balcony is worth exactly three per cent is working with a model just as we are — the only difference is whether they admit it and whether they have their own closed sales behind it.
Land Registry data are delayed. The price data (cenový údaj) are entered only after the registration proceedings (vkladové řízení) have ended. Under § 18(1) of Act No. 256/2013 Coll., on the Land Registry (katastrální zákon), registration may be approved at the earliest after 20 days have elapsed since the information was sent to the owner, and in August 2026, according to the Czech Office for Surveying, Mapping and Cadastre (Český úřad zeměměřický a katastrální, ČÚZK), completing it took 22 days on average nationwide. The most recent transactions are therefore not in the report, and you are always looking into the past, which in a rising market means systematic undervaluation.
For unique properties the method does not work at all. A maisonette (mezonet) with a terrace, a flat with a river view, a villa — there a comparable property sells once every three years and the price cannot be calculated, because there is nothing to calculate it from. In that case we do not promise the client a number, only a range and a procedure for arriving at the price through demand. Some owners do not like hearing this and go where they were given a number straight away — and sometimes it turns out they were right and the market paid more than we expected.
Frequently asked questions
How do I find out what a flat in the neighbourhood sold for? Via remote access to the Land Registry: the report Data on achieved property prices, CZK 50 per output; prices have been recorded since 1 January 2014. But it contains only the price and identification details — you will not learn the condition, the storey or the orientation from it, so the number on its own is not enough for a valuation.
What is the difference between the market price of a flat and the price in an advert? The market price of a flat is the amount two parties agreed on and that ended up in the purchase agreement; the price in an advert is one party’s offer. In the Holešovice example, the difference between completed sales and the price map was 17.8 %.
How much should I sell my flat for if a neighbour is advertising for two million more? Find out how long that advert has been up. A listing that has been on the market for a quarter of a year is not evidence of the price but evidence of the opposite. Base your decision on sales that ended with an entry in the Land Registry.
How many comparable sales are needed? Three are the minimum, five to eight the working number. But quality decides: five transactions with a gross sum of adjustments of up to 20 % tell you more than twenty random sales from the whole city district (městská část).
How long is an estimate valid? In practice, one quarter. At a rate of around 0.9 % a month, the centre of gravity shifts by more than five per cent in half a year, and new transactions are added in the meantime. An estimate older than a quarter of a year is a basis for recalculation, not for a decision.
Key takeaways
An advert is an offer without a second party and, on top of that, a distorted sample — what you mainly see is what has not sold. Sales data cost CZK 50 per output and have been recorded since 2014; the hard part is not obtaining them but selecting the comparables and adjusting them for the differences. The 20 % gross-sum rule is more useful here than any single coefficient, because it excludes by itself the sales that look similar but are not. The output is a range, not a single number — and for properties that have nothing to be compared with, not even the range exists, and the price has to be found another way.